Elevated roadways



17, 1963 u. FINSTERWALDER 3,114,302

' ELEVATED ROADWAYS Filed Jan. 23, 1958 3 Sheets-Sheet 1 IN VEN Tor?Ulrich FINSTEP WAL DER Dec. 17, 1963 u. FINSTERWALDER 3,114,302

ELEVATED ROADWAYS Filed Jan. 23, 1958 3 Sheets-Sheet 2 Fig. 3

IN VEN r o 1 Ulrich PINS rem/A I. vs I? Dec. 17, 1963 u. FINSTERWALDER3,114,302

ELEVATED ROADWAYS Filed Jan. 23, 1958 3 Sheets-Sheet 3 Fig. 5

Fig. 7

IN VEN TO I? Ulrich FINSTERHA L DER United States Patent 3,114,302ELEVATED ROADWAYS Ulrich Finst-erwalder, 8 Pagodenburgstrasse,Obermenzlug, Munich, Germany, assignor to Erich Lubhert, Eugen Schulz,Reinhard Jecht, Egon Reif, and Ulrich Finsterwalder, partners ofDyckerholt dc Widrnaun llommanditgesellschaft, Munich, Germany FiledIan. 23, 1953, Ser. No. 710,720 5 Claims. (Cl. 94-1) The presentinvention relates to elevated roads of concrete constructed in themanner of bridges.

The traffic increase in modern times, particularly in large towns, makesit necessary to construct roads for fast traffic, said roads beingpreferably constructed as bridges. Owing to the density of the traffic,especially wide bridges are required, since it is necessary for afour-lane roadway to allow 25 meters and for a six-lane roadway to allow31 meters width.

In attempting to solve this problem, constructions of reinforcedconcrete have recently been developed, particularly in U.S.A., whichgenerally consist of slabs or sections mounted on columns, cross girdersand main girders. The normal span amounts to 15 meters and the spacebetween the columns in the transverse direction amounts to 4 meters,with the result that it is necessary to arrange 7 columns and moreadjacent to one another in any one cross section of the bridge roadway.Cross girders are laid across these columns and the roadway is tensionedas a plate girder by way of the cross girders. Under the roadway thereis thus a plurality of supports, a feature which is highlyunsatisfactory from the aesthetic point of view and is also a seriousobstacle to the satisfactory utilisation of the space under the bridge.

The primary object of the present invention is to provide a bridge-likeelevated road of concrete wherein these disadvantages are avoided.

The roadway according to the present invention consists of adjacentseries of unitary concrete slabs or sections which project widely fromsupporting columns, are rectangular in plan and are initially tensionedin the axial and transverse directions with the tension bars arrangedpreferably in the upper region of the slabs or sections, each of whichis divided into a number, preferably four, of coherent rectangular orsubstantially rectangular parts, which increase in thickness downwardlyfrom the peripheral edges towards the center of the section in themanner of a mushroom head and, at their center point, rest on rib-likejoists or beams which project diagonally outwardly from a supportingcolumn in directions towards the edges of the section.

The simplest shape in plan view of the said mushroomhead-like structure,is that of a square. If the bridge road is 25 meters wide, this slab orsection covers a ground surface of 25 x 25 m. It projects freely in bothdirections from a point in the center of the square. The slab of 25 x 25in. surface area is 25 cm. thick and is divided into four quadrants of12.5 x 12.5 m. surface area each of which in turn increases in thicknessfrom the outer corner towards the center and is supported by thediagonal rib which projects from the center support for the slab orsection as a whole and terminates in the center of the section.

While retaining the multi-partite mushroom head, the roadway slab mayhowever have an oblong outline, a feature which is suitable for exampleat junctions where the roads cross at an angle other than 90.

Where it is desired that the trafiic along a roadway should move in onedirection only, the road sections may be arranged on separatesuper-structures. In such event each individual slab or section isnarrower and similarly of oblong form, but is subdivided into only twocoherent a ussz Patented Dec. 17., 1963 quadrant parts which likewiseincrease downwardly in thickness from the edges towards the center inthe manner of a mushroom head and the centers of which rest on riblikejoists projecting from the supporting column in a direction parallelwith the longer side of the oblong section.

Further features and advantageous properties of the present inventionwill be apparent from the following description of two embodiments ofthe present invention which are illustrated in the accompanyingdrawings.

In the drawings;

FIGURE 1 is a View of a bridge-like elevated roadway Constructed inaccordance with the present invention,

FIGURE 2 is a corresponding inverted plan view showing the column-likesupport in section,

FIGURE 3 is a section taken on the line IIIIII of FIGURE 2,

FIGURE 4 is a section taken on the line IVIV of FIGURE 2,

FIGURE 5 is a perspective view of a section of the bridge-like elevatedroad having a modified form of column,

FIGURE 6 is a front elevation of an embodiment of the bridge-likeelevated roadway, the individual slabs or sections of which are ofoblong shape,

FIGURE 7 is an inverted plan view of FIGURE 6.

In the embodiment of the bridge-like form of concrete elevated roadwayshown in FIGURES 15, the individual slabs or sections 1 forming theroadway, have a square shape in plan and are provided in the axial andtransverse directions with tensioning reinforcements (not shown). Eachslab or section is sub-divided into four coherent quadrant parts ofequal size, the undersides of which have mushroom-like thickenedportions 2 extending from the edges of the parts towards the center ofthe slab or section, where the parts have maximum thickness. From thecolumn-like strongly constructed center support 3, rib-like girders,joists or beams 4 project diagonally of the part members in the mannerof cantilevers and terminate in the center of the latter, communicatingwith the mushroom-like thickened portions 2.

In the construction illustrated in FIGURE 5, the column-like centersupport is divided into four symmetrical individual supports 3', thespace between which may be used for any desired purpose, such asgarages, business premises, shops and the like.

In the modification shown in FIGURES 6 and 7 two adjacently parallelroadways are arranged on separate superstructures 1a, 1b. The roadwayslab or section of each superstructure is oblong in plan and consists oftwo integral or coherent quadrant-like parts. Each of the columns 3a and3b for these separate sections is provided in the center of the contactline between the coherent parts. Rib-like joists 4a, 4b projecting fromthe columns 3a., 3b extend parallel to the longitudinal sides of theoblong roadway slabs and terminate in the mushroom-like thickenedportions 2a, 2b of the parts.

Should the bridge-like elevated road extend along a curve, theindividual sections or slabs have a shape in plan which is onlyapproximately rectangular, that is to say they resemble the shape of atrapezium or 21 segment of a circle.

In the case of elevated roadways of the bridge type which are located ata low height above the level .of the street network, it is necessary toarrange parting lines centrally between two successive supports. In thiscase it is advisable to choose a construction which absorbs transverseforces but leaves room for relative axial movement. I If the supportsare comparatively high it is possible. to dispense with joints betweentwo succes-' sive supports, by virtue of the elasticity of the supports.

large spaced intervals. Clearly the jutting out ribs may interengagewith the supports in various ways.

By means of the present invention roadways may be constructed atsubstantial heights with a minimum of concrete at the centers of thequadrants and on the support, said constructions making it possible toarrange a square network of steel bars immediately under the top facesof the roadway slabs or sections. This network forms the mainreinforcement of the entire supporting framework. It is advisable forthis reinforcing network to be initially tensioned.

Owing to the concentration of the said reinforcements in the centerareas of the quadrants and on the supporting column, the bending momentsarising from the weight of the sections are very greatly reducedrelatively to continuous slabs currently used. The effect of this isthat the necessary quantity of steel required for the reinforcements issurprisingly small. The shuttering is simple as it deviates onlyslightly from the plane surface and in its layout only projects to asmall extent beyond the ground surface to be covered.

The supporting framework of the roadway is distinguished by the factthat it is easy to survey since the series of column-like supports maybe perceived not only in the axial and transverse direction but also inperspective, i.e. in any desired direction of viewing. The

comparatively great height of the construction above the support, whichis the basis of the economy of the construction, is not apparentoptically, since it is limited to the supporting point. The space underthe roadway is completely free and can be widely utilised for otherpurposes.

It will be appreciated that numerous variations or modifications of theconstructions described and illustrated in the drawings may be adoptedwithout departing from the scope and spirit of the invention. Thespecification and drawin s accordingly should be regarded as anillustrative rather than a restrictive sense.

I claim:

1. An elevated concrete roadway structure comprising structural unitsaligned with one another and provided with longitudinal and transversereinforcing means and being each defined by a plurality of adjacentsubstantialiy rectangular sections formin a part of a roadway and acolumn providing support at one edge portion of each of said pluralityof adjacent sections substantially at the center of gravity of thestructural unit, each said section having a freely supported girderconformation extending cantilever fashion from said column centrally ofthe bottom portion of the section and decreasing in thickness outwardlyof said column, each said section having a bottom portion increasing inthickness inwardly from each of the peripheral borders of the sectiontoward the mid-portion of said section and of said girder conformationin the manner of an inverted pyramid with the sides of said pyramidmerging at the vertex of the pyramid with said girder conformationsubstantially centrally of said section in an area intermediate saidcolumn and a free outer edge portion of said section.

2. An elevated concrete roadway structure comprising structural unitsaligned with one another and provided with longitudinal and transversereinforcing means and being each defined by a plurality of adjacentsubstantially rectangular sections forming a part of a roadway and acolumn providing support at one edge portion of each of said pluralityof adjacent sections substantially at the center of gravity of thestructural unit, each said section having a freely supported girderconformation extending cantilever fashion from said column centrally anddiagonally of the bottom portion of the section and decreasing inthickness outwardly of said column, each said section having a bottomportion increasing in thickness inwardly from each of the peripheralberders of the section toward the mid-portion of said section and ofsaid girder conformation in the manner of an inverted pyramid with thesides of said pyramid merging at the vertex of the pyramid with saidgirder conformation substantially centrally of said section in an areaintermediate said column and a free outer edge portion of said section.

3. An elevated concrete roadway structure comprising structural unitsaligned with one another and provided with longitudinal and transversereinforcing means and being each defined by a plurality of adjacentsubstantially rectangular sections forming a part of a roadway and acolumn providing support at one edge portion of each of said pluralityof adjacent sections substantially at the center of gravity of thestructural unit, each said section having a freely supported girderconformation extending cantilever fashion from said column centrally andlongitudinally of the bottom portion of the section and decreasing inthickness outwardly of said column, each said section having a bottomportion increasing in thickness inwardly from each of the peripheralborders of the section toward the mid-portion of said section and ofsaid girder conformation in the manner of an inverted pyramid with thesides of said pyramid merging at the vertex of the pyramid with saidgirder conformation substantially centrally of said section in an areaintermediate said column and a free outer edge portion of said section.

4. An elevated concrete roadway structure comprising structural unitsaligned with one another and provided with longitudinal and transversereinforcing means and being each defined by a plurality of adjacentsubstantially rectangular sections forming a part of a roadway and acolumn providing support at one edge portion of each of said pluralityof adjacent sections substantially at the center of gravity of thestructural unit, each said section having a freely supported girderconformation extending cantilever fashion from said column centrally anddiagonally of the bottom portion of the section and decreasing inthickness outwardly of said column, each said section having a bottomportion increasing in thickness inwardly from each of the peripheralborders of the section toward the mid-portion of said section and ofsaid girder conformation in the manner of an inverted pyramid with thesides of said pyramid merging at the vertex of the pyramid with saidgirder conformation substantially centrally of said section in an areaintermediate said column and a free outer edge portion of said section,said longitudinal reinforcing means of a plurality of adjacentstructural units being continuous in the upper part of the roadway todefine an uninterrupted roadway.

5. An elevated concrete roadway structure comprising structural unitsaligned with one another and provided with longitudinal and transversereinforcing means and being each defined by a plurality of adjacentsubstantially rectangular sections forming a part of a roadway and acolumn providing support at one edge portion of each of said pluralityof adjacent sections substantially at the center of gravity of thestructural unit, each said section having a freely supported girderconformation extending cantilever fashion from said column centrally andlongitudinally of the bottom portion of the section and decreasing inthickness outwardly of said col umn, each said section having a bottomportion increasing in thickness inwardly from each of the peripheralborders of the section toward the mid-portion of said section and ofsaid girder conformation in the manner of an inverted pyramid with thesides of said pyramid merging at the vertex of the pyramid with saidgirder conformation substantially centrally of said section in an areaintermediate said column and a free outer edge portion of said section,said longitudinal reinforcing means of a plurality of adjacentstructural units being References Cited in the file of this patentUNITED STATES PATENTS Martin Nov. 19, 1912 5 6 Foster May 5, 1925MacMillan Mar. 29, 1932 Workman Mar. 24, 1936 FOREIGN PATENTS GreatBritain Feb. 2, 1909 UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent N00 3 1l4 302 December 17 1963 Ulrich Finsterwalder Itis hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

In the grant, lines 3 and 1 1, and in the heading to the printedspecification, line 5 for "Egon Reiffl. each occurrence, read Egon RufSigned and sealed this 16th day of June 1964,

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

1. AN ELEVATED CONCRETE ROADWAY STRUCTURE COMPRISING STRUCTURAL UNITSALIGNED WITH ONE ANOTHER AND PROVIDED WITH LONGITUDINAL AND TRANSVERSEREINFORCING MEANS AND BEING EACH DEFINED BY A PLURALITY OF ADJACENTSUBSTANTIALLY RECTANGULAR SECTIONS FORMING A PART OF A ROADWAY AND ACOLUMN PROVIDING SUPPORT AT ONE EDGE PORTION OF EACH OF SAID PLURALITYOF ADJACENT SECTIONS SUBSTANTIALLY AT THE CENTER OF GRAVITY OF THESTRUCTURAL UNIT, EACH SAID SECTION HAVING A FREELY SUPPORTED GRIDERCONFORMATION EXTENDING CANTILEVER FASHION FROM SAID COLUMN CENTRALLY OFTHE BOTTOM PORTION OF THE SECTION AND DECREASING IN THICKNESS OUTWARDLYOF SAID COLUMN, EACH SAID SECTION HAVING A BOTTOM PORTION INCREASING INTHICKNESS INWARDLY FROM EACH OF THE PERIPHERAL BORDERS OF THE SECTIONTOWARD THE MID-PORTION OF SAID SECTION AND OF SAID GRIDER CONFORMATIONIN THE MANNER OF AN INVERTED PYRAMID WITH THE SIDES OF SAID PYRAMIDMERGING AT THE VERTEX OF THE PYRAMID WITH SAID GIRDER CONFORMATIONSUBSTANTIALLY CENTRALLY OF SAID SECTION IN AN AREA INTERMEDIATE SAIDCOLUMN AND A FREE OUTER EDGE PORTION OF SAID SECTION.